Question about default context node

[Michael Rys]

While not XQJ related: The XQuery implementation on the XML Datatype in
SQL Server 2005 operates on the context item.

Best regards
Michael

> -----Original Message-----
> From: http://xquery.com/mailman/listinfo/talk [mailto:http://xquery.com/mailman/listinfo/talk] On
Behalf
> Of Michael Kay
> Sent: Friday, September 17, 2004 2:23 PM
> To: 'Alex'; http://xquery.com/mailman/listinfo/talk
> Subject: RE:  Question about default context node
> 
> >
> > Which mechanism would you recommend for input data, external var or
> > context node? My use case would be one XML document in, one XML
> > document out, similar to an XSLT transformation with JAXP/TRAX.
> 
> Whatever is most convenient. There's no real difference internally.
> >
> > Do you know if other implementations also support the context node
> > concept?
> 
> I haven't been tracking other implementations, sorry!
> 
> Michael Kay
> 
> 
> >
> > thanks,
> > alex
> >
> >
> > > The key thing here is appendix C.2, which indicates that there is
no
> > > language-predefined default for the initial value of the context
> > item, but
> > > that a value can be supplied "by the implementation" - which in
> > practice
> > > means that the implementation can provide means for the user to
set
> > a value
> > > via an API. An implementation could if it wished always set this
to
> > a fixed
> > > value (for example it could always set the initial context item to
> > the
> > > integer zero or to a random number) but that seems an unlikely
> > choice to
> > > make. The language spec is very careful to steer clear of
> > API issues.
> > >
> > > As for XQJ, I think there are lots of things missing from the
> > current drafts
> > > of XQJ. I suspect (I certainly hope) that the final spec will move
> > on a fair
> > > bit from the draft that we've seen.
> > >
> > > Michael Kay
> > >
> > > > -----Original Message-----
> > > > From: http://xquery.com/mailman/listinfo/talk
> > > > [mailto:http://xquery.com/mailman/listinfo/talk] On Behalf Of Alex
> > > > Sent: 17 September 2004 18:27
> > > > To: http://xquery.com/mailman/listinfo/talk
> > > > Subject:  Question about default context node
> > > >
> > > > Hi,
> > > >
> > > > is a default context node part of the XQuery standard?
> > I'm getting
> > > > conflicting messages. For one, I heard statements that you
> > > > need to use
> > > > doc(), collection() or external variables to pass in data to an
> > > > XQuery. On the other hand, implementations like Saxon provide
> > methods
> > > > like setContextNode() in their Java API so a simple XPath
> > like /a/b/c
> > > > is also a valid XQuery that makes sense. I like the context node
> > > > option because of its simplicity but am not sure if it's
> > standard.
> > I
> > > > haven't seen support for it in XQJ.
> > > >
> > > > I would appreciate any clarification and references to the
XQuery
> > > > standard concerning context nodes set from the API.
> > > >
> > > > Thanks,
> > > > alex
> > > > _______________________________________________
> > > > http://xquery.com/mailman/listinfo/talk
> > > > http://xquery.com/mailman/listinfo/talk
> > > >
> > >
> > >
> > >
> >
> > --
> >
> > _______________________________________________
> > http://xquery.com/mailman/listinfo/talk
> > http://xquery.com/mailman/listinfo/talk
> >
> 
> _______________________________________________
> http://xquery.com/mailman/listinfo/talk
> http://xquery.com/mailman/listinfo/talk